body {
    font-family: Helvetica, Arial, serif;
    background-color: #679ED2;
}


h1 {
    font-size: 3em;
    margin: auto;
    padding: 20px;
}

h2 {
    padding: 10px;
    font-size: 2em;
}

#nav li {
    float: left;
    padding: 10px 0px 10px 5px;
    width: 105px;
    box-shadow: 10px 10px 0 0 rgba(0, 0, 0, 0.3);
}

#nav li:hover {
    cursor: pointer;
}

#nav li:nth-child(3) {
    width: 50px;
}

#nav li:nth-child(4) {
    width: 230px;
}

#nav li:nth-child(5) {
    width: 115px;
}

.unselected {
    background-color: #DFDFDF;
}

.selected {
    background-color: #EFEFEF;
}

#heading {
    width: 740px;
    margin: auto;
    margin-bottom: 20px;
    text-align: center;
    background-color: #EFEFEF;
    box-shadow: 10px 10px 0 0 rgba(0, 0, 0, 0.3);
}

#tabs {
    margin: auto;
    width: 740px;
}

#tabs h2 {
    padding: 30px 50px 30px 50px;
}

#tabs p {
    padding: 10px 50px 30px 50px; 
    width: 640px;
}

.video-box {
    padding: 50px;
    margin: auto;
}

.show-tab {
    background-color: #EFEFEF;
    position: relative;
    top: 36px;
    visibility: visible;
    box-shadow: 10px 10px 0 0 rgba(0, 0, 0, 0.3);
}

.hide-tab {
    position: absolute;
    left: -10000px;
    visibility: hidden;
}